My Note: Yoga, as well as many other Esoteric Traditions before Yoga, knew of this subject millennia ago, when talking about the Mind of All that IT is and the fact the entire universe (together with T/S) is a mindscape. But science has no shame, taking many old esoteric discoveries and making them look new. Buddha talks of Shunya, which actually translates as Void or Black Hole! He knew also the Void absorbs man's mind when he dies. And he knew also man's mind is not actually lost but rather stored in the Mind Cloud of our universe for the next life to come! But just very few can assimilate such esoteric vision, even today, they are called yogis, and the real ones are very few in number!
Black holes are cosmic bodies consuming the nearby mass to grow larger and larger. The black holes exert such a strong gravitational force that not even light can escape, and they are able to distort the very fabric of space and slow the passage of time. These are very real objects, but they embody a very significant mystery. Black holes are said to absorb matter and never let it go. The matter simply disappears inside the black hole. But matter is more than simply matter, it is also information. For instance, if I have a single atom of hydrogen, I have a proton and electron. That's matter. But there is also information in how they are connected. Are they near one another, or far apart?
The information component is even more important in, say, a piece of fruit, which cannot be what it is without the information that tells us not how many protons, neutron and electrons are there, but also how they are arranged. Without this information an apple, for example, wouldn't be an apple at all. Ultimately, it is information that is at the heart of each define mass in existence.
That's why according to the rules of quantum mechanics, information should never be lost, not even if it gets sucked inside the black hole. This is because of two premises: causality and reversibility. Taken together, it means that effects have causes, and those causes can be undone. For example, you can break a glass and then find all the pieces and glue it back together. Yet, these two premises don't hold for a classical black hole, in which the information is permanently and irreversibly lost as it enters the black hole.
Note that information being lost isn't the same as matter being lost, the same like the information in your computer is not lost if your computer is wrecked -- you have it on your memory stick or other storage device. In the 1970s, Hawking postulated what is now called Hawking radiation, which in principle, cause black holes eventually to evaporate as the radiation carries away energy. However, Hawking radiation should be completely independent of the matter absorbed by a black hole. So, information really does appear to be lost, in complete contradiction of quantum theory.
This is where Hawking's later announcement comes in. He is saying that he can solve the conundrum. He is opposing the claim that the black hole destroys the information, because the information never actually falls into the black hole, being rather held on the black hole's surface -- the event horizon.
This is an intriguing thought and is analogous to how holograms are made. Holograms are two-dimensional sheets of, for example, plastic that can make three-dimensional images. All of the information of three dimensions is encoded in the two dimensional plastic. (By the way, there are some who hypothesize that our entire universe is a hologram!)
It is difficult to properly evaluate Hawking's announcement. The claim as it has been described is not very precise. There is no paper published on the idea, nor has the idea passed peer review. In fact, scientists who attended the conference are still trying to absorb the idea and to cast it in a mathematical language so that the implication can be assessed.
Hawking developed this concept in collaboration with Malcolm Perry of Cambridge University and Andrew Strominger of Harvard University. They plan to submit a paper in a month or so. That's when the real evaluation of the proposal can begin.
While everyone would much prefer to hear about a definitive advancement in science, the actual process of developing scientific ideas can be both intellectually stimulating and thoroughly messy. Stephen Hawking's new ideas are certainly interesting and may point us in the right direction. But we will have to wait a bit longer to solve the enigma of what happens when information confronts a black hole. Sit tight, we're on a very long journey.